I've had the dreaded death rattle for the last few months, so I've been acquiring parts I expect I'll need to replace the supercharger. I was pretty sure I had most of what I would need (I haven't ordered the supercharger yet) but I know in jobs like this, sometimes the unexpected happens. I figured I would pull the supercharger and create a parts list of things I hadn't though of (crank sensor gasket, bypass valve sleeve...) then order them so that installing the new supercharger should go relatively smooth.

When I went to disconnect the battery prior to removing the alternator, I found my battery sitting in about 6" of water. I had just replaced this battery in October, so I know it was dry then. Since then we had a rain storm (a noteworthy day here in the desert) a few weeks ago, so somehow rain got inside the boot.

Now to figure out how. My first thought is clogged sunroof drains but I have noticed the past year or so, that after rain events (or car washing), there is water in the hatch. I can hold the hatch in a certain position to let it drain on the ground. I had been meaning to investigate, but you know. So I wonder if my glass (it's original) is leaking at a seal somewhere.

I started to tear the boot apart to search for evidence but I decided to wait until I have the car running again so I can drive it to a water hose to spray my car. Are there any known water leak points at the rear of R53's?

With the holiday's, it's going to be a couple of weeks until I work on my car again. Rain isn't very likely, but now I know there is a serious leak problem so I can take preventative measures if rain is in our forecast.

 

The battery box has a drain hole from the factory but for some stupid reason they plugged it.

Remove the plug and water will drain out.

I was totally horrified when I discovered an inch or so of standing water in my battery box a few months ago after very heavy rains.

I don't have a sunroof --- in my case it was the silly white clips which hold the rear trim on. Such a dumb design. I added sealant and it did the trick.

There are myriad other entry areas in the boot though, all worth checking:

3rd brake light seal

hatch handle seal

brake light seals

rear wiper grommet

This MINI is love/hate for me.

I love the hell out of it but also regularly curse it.

LOL

 

As mentionned, brake lights if the drains are fine.

But I'll add one from my personal experience: the antenna!!! I had the sunroof drain issue years ago (front passenger side), but I also had a leak from the antenna. It's two piece with a gasket, so water was making its way inside the antenna, then leaking by the wires.

 

Those are all great tips! Thanks so much!

 

I can relate. I did some work on my car over the weekend.......went to disconnect the battery, and found the same thing! Battery sitting in an inch of water! Sounds like I need to start checking things.......